Place onion, sugar, and olive oil in a large nonstick skillet over medium heat, stirring often for 20 to 25 minutes, or until onions are fragrant and light brown in color.

Stir in water, vinegar, and salt. Turn temperature down to low and allow the onions mixture to simmer until thick.

Bison burgers:

Preheat a gas or charcoal grill to 475 to 500 degrees F.

Divide ground bison up into 4 patties, about an inch thick and 4 inches in diameter. Sprinkle each patty with salt and pepper and place on a non-stick surface. Cover with plastic wrap and allow at least one hour in the refrigerator to set. (Optional)

Place patties on a pre-heated grill and cook for 4 minutes.

Flip patties over and cook another 4 or 5 minutes, or until internal temperature reaches 160.